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Interstellar and Circumstellar Medium

Evolved-star dust production rates for the Large Magellanic Cloud from Riebel, Srinivasan, Sargent et al. (2012)

The distribution of dust production rates (DPRs) from the entire population of red supergiant (RSG) and asymptotic giant branch (AGB) stars in the Large Magellanic Cloud (LMC). The DPRs were obtained by fitting pre-computed models from the GRAMS (Grid of RSG and AGB ModelS, Sargent et al. 2011, Srinivasan et al. 2011) set to the observed spectral energy distributions of our evolved star candidates. The fitting technique determines of the chemical type (O-rich or C-rich) and the luminosity and DPR for each source, along with uncertainty estimates for these parameters.
The figure above shows that while less dusty O-rich AGBs and RSG stars make up more than three-quarters of the LMC evolved-star population, their total dust contribution is only about one-fifth. In comparison, only 5% of the sample are classified as extreme AGBs (consisting of very dusty O-rich and C-rich stars), but they contribute almost three-fourths of the total dust budget.
AGB stars contribute 2.5 times as much carbonaceous dust as O-rich dust to the interstellar medium of the LMC. A similar study for the Small Magellanic Cloud is in progress (Srinivasan et al. 2013).